In my above-identified copending application I have disclosed a mining lamp with an elongate bulb in the form of a fluroescent tube mounted on a base plate and enveloped by a light-transmissive vaulted cover which is snap-fitted onto that plate so as to form an airtight seal therewith while being readily detachable to enable replacement of the bulb. Such a lamp, when horizontally positioned, radiates light in all directions above the plane of its base plate and can therefore be used to illuminate the roof and the walls of an underground room.
When a tunnel is being driven forward by automatic excavating equipment on a mine face, continuous illumination of that mine face is desirable. At the same time it becomes necessary to protect the lamp or lamps illuminating the mine face from lumps of solid matter, such as rock fragments, thrown backward by the excavating tool onto a conveyor or into a channel serving for the transportation of these lumps to a gallery paralleling the direction of advance.